References

The X-Files (1993)
(TV Series)
Knox mentions the series while talking to Dooley

The Hitchhiker's Guide to the Galaxy (2005)
The music score is very similar to the one of "Hitchhiker's Guide to the Galaxy, The (2005)", if anything as a homage. Furthermore, a space ship in the form of a shoe is a paraphrase of how the space ship "The Heart of Gold" was originally depicted as looking, in the novel version of "The Hitchhiker's Guide".

Shrek the Third (2007)
Billboard can be seen when Dave hits the streets of New York at the beginning of the movie

Surf's Up (2007)
When Dave joins the "urban camper" a poster or ad with a motive from the movie can be seen in the shop window to the right.

Live Free or Die Hard (2007)
Billboard can be seen when Dave hits the streets of New York at the beginning of the movie

Ratatouille (2007)
Billboard can be seen shortly when it begins to rain in the evening.